Dr. Aaron Frederick Severson

Research Interests

Education: Ph.D., Biology, University of Oregon, 2001

B.S., Zoology, Molecular Biology, University of Wisconsin, 1994

Brief Bio: In all organisms, accurate transmission of the genome during cell division is essential to prevent genetic instability. This is especially true during meiosis, the process that reduces genome copy number, or ploidy, from two in diploid germline stem cells to one in each haploid gamete. Defects in meiosis affect all cells of an embryo and profoundly impact health: it is estimated that over 30% of human zygotes have abnormal chromosomal content at conception, and such aneuploidies are the leading known cause of miscarriages and birth defects. The best known viable aneuploidy, trisomy 21, causes Down syndrome. I use a microscopic roundworm called Caenorhabditis elegans to study how gametes inherit exactly one copy of every chromosome. My research interests encompass events that occur early in meiosis, such as DNA replication, generation of sister chromatid cohesion, homolog pairing, and crossover recombination, as well as those that occur late in meiosis to establish the unique pattern of chromosome segregation that occurs during meiosis and is crucial for the reduction of ploidy. Because the mechanism of meiosis is widely conserved among eukaryotes, the knowledge we generate from our studies of the lowly worm is relevant to understanding normal gametogenesis in humans, as well as the errors in this process that underlie reproductive disease.

Severson, A.F., D.L. Baillie, and B. Bowerman. 2002. A Formin Homology protein and a Profilin are required for cytokinesis and Arp2/3-independent assembly of cortical microfilaments in C. elegans. Current Biol. 12:2066-2075.